DaveB

Posted 25 March 2011 - 09:06 AM

DaveB

Hall of Fame

Validated Member

1,122 posts

Gender:Not Telling

Location:Redlands, CA

United States

I haven't tested this with multi-band rasters, but it should work.
Open just the raster in ArcMap, with no other data. Then use the Export Map command from the File menu. If you do this from data view you can set some options in the output file including writing a world file for jpg or tiff formats or writing a geotiff. I have used this method to "compress" multiple rasters, such as a hillshade and hypsometry, into a single file.

M.Denil

Posted 08 April 2011 - 01:34 PM

M.Denil

Key Contributor

Validated Member

56 posts

United States

You say you want "to merge these three bands to one."

Just what do you mean by that? If the three bands are merged to one, it will no longer be a three color raster, just a single greyscale image. It will also likely be of questionable use, just smouched together (smouched may not be the correct technical term...)

One can go the other way, merging three single band geyscale rasters into an RGB composite using the Arc
CompositeBands_management <in_rasters;in_rasters...> <out_raster>
tool: it puts out .bmp, .img, .jpg, .jp2, .png, .tif, GRID, or geodatabase rasters.

What it sounds like you want, however, begins with splitting the image into individual bands:

Splitting the channels can be done with the Arc tool:
RasterToOtherFormat_conversion <Input_Rasters; Input_Rasters...> <Output_Workspace> {GRID}
Outputting to a GRID with this tool will produce a GRID stack, and three component GRIDs

The three component GRIDs will be one each of the three channels. Each a single band greyscale image.

I suppose you can go on to merge these together, using any of a range of raster tools, if that is what you really wanted to do. Again, just why you needed to do this was unclear.

By the by, one can also split the channels in Photoshop or Corel PhotoPaint, but you will have to georeference the output images after. That, however, is not too hard, since you have the source image for a reference.

raj nagi

Posted 06 May 2011 - 06:07 PM

raj nagi

Newbie

New Member

5 posts

Gender:Male

United States

You can do this through Image Analysis Window (http://help.arcgis.c...000000m7000000/). Open Image Analysis window by clicking Windows on main menu and then Image Analysis. Now in Image Analysis window click the color aerial imagery and under processing section of Image analysis window, click clip. This will generate a new temporary layer and add to the TOC. Now right click the layer and click properties. In the layer properties window click the ‘Functions’ tab and right click the clip function and insert grayscale function (http://help.arcgis.c...0004w000000.htm). This will open a dialog box where you can give different weight to each band. This will give one band image, which is temporary. You can make this permanent by right clicking the layer and then Data -> Export Data. You would need to provide location, name and format of the file.
Hope this helps!